Multiwheel-propelling mechanism for motor vehicles



p 27' J. M. 'rHoRP MULTIWHEEL PROPELLING MECHANISM FOR MOTOR VEHICLESFiled Aug. 7. 1924 INI/ENTOR! Patented Sept. 27, 1927. Y i

UNITEDv STATES JAMES MADISON THORP, OF ALA'JVJIEIJA,v CALIFORNIA.

MULTIWHEEL-PROPELLING' MECHANISM FOR MOTOR VEHICLES.

Application led August 7,V 1924. Serial No. 730,694.

Thevfunction of the present invention is similar to that 'disclosed inLetters Patent issued to me Oct. 16, 1923', No. 1,471,295 which operatesthrough worm gearing with the drive shaft subject to vertical movementas the wheels ride over uneven surfaces; whilethe one described belowmaintains the 'drive shaft in a straight line, the worm drive beingomitted` and double reduction gears substituted. p .i

Other advantages are the spur gearing in the two-to-one differentialvand the straight line final driveshaft at load position.- t

Figure 1 of the drawings is a sectional elevation through a motorvehicle embodying my invention, showing the housings onlyof themechanism; Fig. 2 an enlarged sectional elevationy in detail, throughthe line shaft and final drive shafts; Fig. 3 a top view of one unit ofthe drive; an'd Fig. 4 a cross section through 2 2 of the two-to-onedifferential. l y

Y Similar characters of reference denote similar parts throughout theseveral vi-ews.

In the detail drawings "shaft Yand, gear bearings are omitted Vas theytend to obstruct the view .of important parts, its is understoodhowever, that 'such' omission can vbe readily supplied by those expertin the art.

Referring to the drawings, thevline shaft is composed of three sections,1 2 and 3 coaxially abutting at 4 and 5; upon the shaft 1 is mounted thetwo-to-one differential 6, shaft 2 carries the one-to-one differential 7and shaft 3 the pinion 8; each of these units operates a final driveshaft 9 1() and 11 respectively.

I will now describe the invention as shown in the drawings, it beingunderstood that, although I describe a mechanism for propelling threeaxles, the addition of one unit, as hereinafter described, will fit theline shaft for driving four axles, or by omitting one unit, two axlesmay be driven.

In this arrangement I employ helical pinions and gears to deliver powerfrom the line shaft to each of the driven units, and ineline the finaldrive shafts so that at full load the shafts broken by the universaljoint A will line up and in general relieve the universal knuckle fromunnecessary movement.

Shaft 1 is keyed to the spider 13 upon which is mounted the planetpinions 15, these pinions mesh with the sleeve-gear 16 on the inner sideand with the internal gear 17 on the outer side, the sleeve of the gear16 is keyed to a` driving pinion v18, the shaft 2 is fixed to the gear17 at one end and at the other to a second spider 19 upon which ismounted the planet pinions 20 which are meshed with a seCondsleeve-gear21 and a similar gear 22 to which the shaft 3 is fixed; the sleeve ofgear 21 is keyed to the pinion 23 and the shaft 3 to. the pinion 8.

The final drive shafts are made flexible by means of the universaljoints A, and the housings of these shafts act as torque arms and arepivoted at C in the usual manner.y

' In operation: Power from the motor 12 revolves the shaft 1 and thespider 13, the pinions 15, not turning on their axis. but being meshedwith the gears 16 and 17 will ro'- tate them both at the same speed asthe spider, one-third of the power from the line shaft being transmittedthrough the sleeve Yto'V the pinion 18and to the gear 24 and to thefinal drive shaft 9 then through the vusual gears and axle differentialto the axle y25.

The gear 17 will deliver two-thirdsV of the power to the shaft 2 whichrotates the spider 19. and ythe pinions 2O not turning on their axiscarrv another third of the power through the sleeve an'd its gear to thepinion 23, gear 26 and final drive shaft 10 to the next axle in theseries. The gear 22 operating the shaft 3 and pinion 8 and gear 27 delivers the remaining third of the power to the third axle. A*

It is obvious. to one skilled in the art. that the function of the gearsin a differential is not to transmit power through their rotation but tostrike balance between driven members. A

In the case now under considerationwe have to balance the 'driving powerof the motor so as to divide it equally between three axles. i

Special attention is called to the gear ratios in the differential 6.the sleeve-gear 16 being half the 'diameter of gear 17, thus traction orinertia of the wheels operated from axle 25 will have a double purchasethroughv the smaller gear and will hold or balance the combined inertiaor tractive force of the other four wheels. Thus in like manner but witha ratio of one to one the differential 7 will balance or divide thestresses between the other two axles.

As mentioned above, four axles may be driven by adding another unitbetween the diderential 6 and the motor, the arrangement of parts beingsimilar but with a gear ratio in the differential of three to one.Likewise by omitting unit 6 and applying the power to shaft Zthedifferential 7 will balance the stresses of the two axles driven fromthe pinions 23 and 8.

l am aware that numerous methods of gearing have been employed in theconstruetion of compensating` mechanism to balance the speed andstresses between two wheels, in such cases however, the power isdelivered to the spider through a gea-r fixed to the peripher)7 of thespider, such methods are not adapted to concentric line shaft operation.

rlhe differential 7 of the drawing is a well known form vas to bevelgears and planet pinions but entirely differentas to application ofpower and function thereof. I therefore reserve the rights to `all suchvariations and alterations as fall within thescope of my invention andthe terms of theV following` claims:

.l claim:

l. A multi-way differential, comprisingr a line shaft divided into anumber of (zo-axially mounted sections, spiders fixed to some of theshaft sections, sleeves mounted on vthe shafts adjacent to the spiders,gears upon the sleeves and upon the shafts, planet pinions mounted onthe spiders and in meshing.: Contact with gears upon .the sleeves andshafts, thedianieter ratio .of the sleeve gears to that `of the shaftgears varying with the number of'axle units to be driven so as tobalance the stresses between the several axles.

`2. In multi-way differentials, a line shaft of two or more eo-axiallymounted sections, a spider fixed to each shaft section but one, a sleevemounted on the A.shaft sections adjacent to each spider, planet pinionsonthe spiders, gears lof varying'ratioson the shafts and sleeves and inmeshing engagement with the planet pinio'ns.V

3. A multi-wheel liner-shaft diiferential, ,comprising a drive shaft, aplanet Vgear spider iixed to the rear end of said drive shaft, asleevehaving a small gear rotatably Ymounted upon said drive shaft .adjacentto said spider, a driven Vshaft mounted concentric with the drive shaft,an internal gear .of greater diameter than the small gear'fixed to saiddriven shaftand cupping over said spider, planet pinions pivotallymounted upon the spider between and meshing` with ,both the small gearand the internalfgear, and a driving gear upon the forward end of thesleeve, for 'the purpose specified.

'4. A multi-wheel propelling mechanism,

,comprising a line shaft` of ,two or more eoaxiallly mounted sections,sleeves, spiders and :gears mounted upon the shaft Vsections in oneofthe shaft sections, .helical ytoothed gears fixed to shafts, that areinclined .to the axis .of said line ,.shaft, V and meshing .with saidhelical toothed pinions, ,the vinclined `compensating arrangement asvdescribed, helical toothed pinions on the sleeves and onV shafts beingadapted to connect vwith land drive a series of vehicle axles.

JAMES Main .isou Tueur;

